Crawler tractors and other types of off-highway implements are typically provided with endless tracks on opposite sides thereof. During operation of the implement, a major source of noise is generated by the metal tracks as they pass over a drive wheel, front idler, and carrier rollers.
A typical track is comprised of a series of metal links. Adjacent ends of the links are pivotally interconnected by a pin and bushing assembly to form an endless chain. The noise generated by the track arises from the bushing and links impacting against the periphery of the wheel, idler, and rollers as the track circulates during moving of the implement. Noise production is transmitted through the implement structure, radiated to the interior and amplified by resonant conditions.
Attempts at reducing the noise level by reducing the mass of the track or by increasing the diameter of the idler wheels for the tracks have been implemented in the past. Tensioning the track as by mounting the drive wheel and idler wheel with their axes resiliently positioned with respect to each other in order to hold the chain or track taut has also been used to reduce the noise level of the track during implement operation. The above efforts notwithstanding, relatively high noise levels continue to be an inherent problem and pose a public nuisance problem during operation of crawler tractors and the like.
Thus, there is a need and a desire for an apparatus capable of reducing the noise level inherent with circulation of an endless track during operation of a crawler tractor and the like.